模拟大气沉降氮在陆地生态系统中的留存及其影响因素  

Modeling the retention of atmospheric deposited nitrogen and influencing factors in terrestrial vegetation ecosystems

作　　者：邓旭 王丽娜 周莹[2] 张泽凌 路浩[2] 唐亚坤[2,3,4] DENG Xu;WANG Lina;ZHOU Ying;ZHANG Zeling;LU Hao;TANG Yakun(College of Forestry,Northwest Agriculture and Forestry University,Yangling 712100,China;College of Soil and Water Conservation Science and Engineering,Northwest Agriculture and Forestry University,Yangling 712100,China;Institute of Soil and Water Conservation,Chinese Academy of Sciences and Ministry of and Water Resources,Yangling 712100,China;Institute of Soil and Water Conservation,Northwest Agriculture and Forestry University,Yangling 712100,China)

机构地区：[1]西北农林科技大学林学院,杨凌712100 [2]西北农林科技大学水土保持科学与工程学院,杨凌712100 [3]中国科学院水水土保持研究所,杨凌712100 [4]西北农林科技大学水土保持研究所,杨凌712100

出　　处：《生态学报》2025年第3期1077-1089,共13页Acta Ecologica Sinica

基　　金：国家自然科学基金(41977425)。

摘　　要：大气氮沉降对陆地生态系统的影响取决于氮在生态系统中的留存量。探明生态系统的氮留存作用对预测全球变化背景下生态系统氮循环具有重要意义,但植物、土壤和生态系统氮留存的影响因素仍不清楚。通过文献搜集对58个野外15N同位素示踪研究的305组观测结果进行综合分析。结果表明:生态系统氮回收率(^(15)N_(rec))为(56.3±1.39)%,且土壤^(15)N_(rec)(40.1±1.17)%显著高于植物^(15)N_(rec)(16.2±0.89)%(P<0.001)。年均温度、年降水量、土壤有机碳、总氮和碳氮比的增加显著增加植物、土壤和生态系统^(15)N_(rec),但土壤pH、施氮量和施氮持续时间的增加却显著降低植物和生态系统^(15)N_(rec)(P<0.05)。上述因素解释了生态系统、植物和土壤^(15)N_(rec)变化的65.0%,61.0%和64.0%。年降水量是影响生态系统、植物和土壤^(15)N_(rec)的最主要因素(P<0.001),年降水量和年均温度构成的气候因素显著影响生态系统、植物和土壤^(15)N_(rec)。研究结果对阐明陆地生态系统氮循环过程,以及维持生态系统的稳定性具有重要意义。The response of terrestrial ecosystems to atmospheric nitrogen deposition is determined by nitrogen retention in ecosystems.Understanding the role of ecosystem nitrogen retention is essential for predicting ecosystem nitrogen cycling in context of global change.However,the drivers of nitrogen retention in plants,soils and ecosystems remain unclear.In this study,we conducted a comprehensive analysis of 305 observations from 58 field sites ultilized 15N isotope tracing studies.The results showed that the percent of ^(15)N recovery(^(15)N_(rec))of the ecosystems was(56.3±1.39)%,and the ^(15)N_(rec) for soils(40.1±1.17)%was significantly higher than that for plants(16.2±0.89)%(P<0.001).Increased in the mean annual temperature,mean annual precipitation,soil organic carbon(C)content,total nitrogen(N)content,and C∶N ratio significantly increased plants,soils,and ecosystems ^(15)N_(rec),while increased in soil pH,N application rate,and N application duration time significantly decreased plants and ecosystems ^(15)N_(rec)(P<0.05).The above factors explained 65.0%,61.0%,and 64.0% of the ecosystems,plants,and soils ^(15)N_(rec).Mean annual precipitation was a pivotal factor affecting ecosystems,plants and soils ^(15)N_(rec)(P<0.001).The climatic factors composed by mean annual precipitation and mean annual temperature significantly influenced ecosystems,plants and soils ^(15)N_(rec).The results of the study can be essential for elucidating the nitrogen cycling in terrestrial ecosystems as well as maintaining the stability of ecosystems.

关 键 词：大气氮沉降 氮循环 生态系统 氮留存 结构方程模型 

分 类 号：S15[农业科学—土壤学]